Rotatable work support for a sewing machine

ABSTRACT

An improved sewing machine including a rotatable sewing table having a curved surface for supporting the material to be sewn and for moving the material into the path of the sewing needle. A novel material supporting member is adapted to be moved axially toward and retracted away from registry with the curved surface of the sewing table.

United States Patent Tinari et al.

[451 Mar. 21, 1972 [54] ROTATABLE WORK SUPPORT FOR A 1,720,658 7 1929 Gail ..112/252 x SEWING MACHINE 2,828,702 4/1958 Hall ...1l2/79.5 2,892,427 6/1959 Winberg... ..112/211 1 Inventors Louis Tinari, 40625 Hampton Street, 2,766,709 10/1956 Stevens ..112/63 Elmhurst, NY. 11373; David H. Kamena, 3 Peach Tree Court, Parsippany, NJ. FOREIGN PATENTS OR APPLICATIONS 07054 41,233 3/1910 Austria ..l12/260 [22] Filed: Aug. 11, 1969 Primary ExaminerPatrick D. Lawson [2]] App! 848966 Assistant ExaminerGeorge H. Krizmanich Attorney-Gerald Weir and Eugene Lieberstein [52] U.S.Cl ...1l2/260, ll2/121.15 [5 l Int. Cl. ..D05b 75/00 [57] ABSTRACT [58] ies ?i ig'gg g% ig An improved sewing machine including a rotatable sewing 21 table having a curved surface for supporting the material to be sewn and for moving the material into the path of the sewing needle. A novel material supporting member is adapted to be [56] References Clted moved axially toward and retracted away from registry with UNITED STATES PATENTS the curved surface of the sewing table.

1,577,649 3/1926 Mark ..1 12/12 1 .24 9 Claims, 2 Drawing Figures 1* Y i V e 261?! g7 g4 50 7, at .2443

PATENTEDHARZI I972 INVENTYORS LOUIS E.TINARI DAVID H. KAMENA BY ATTORNEY ROTATABLE WORK SUPPORT FOR A SEWING MACHINE This invention relates to sewing machines and more particularly to improvements for feeding material to be sewn into the path of the sewing needle. The invention is particularly useful when sewing garments having a curved configuration such as cuffs, collars and the like. Conventional sewing machines having flat sewing surfaces require considerable care when sewing garments having a curved configuration in order to avoid puckering of the material.

Moreover, much of the sewing carried on in the garment industry requires considerable operator skill in aligning and guiding the garments to be sewn in order to maintain a uniform stitch pattern. Operator skill is also required to rapidly position the garments to be sewn on the sewing table.

It is an object of the present invention to provide an improved sewing machine capable of operation by a relatively inexperienced operator.

Another object of the invention is to provide a sewing machine particularly adapted for sewing garments having a curved configuration such as cuffs, collars and the like.

Yet another object of the invention is to provide a sewing machine wherein the garment to be sewn may be rapidly fed into the machine, clamped in place and thereafter sewn with a minimum of operator skill.

These and other objects and advantages of the invention will be achieved according to the invention as will be apparent to those skilled in the art.

In the drawing:

FIG. 1 is a side elevational view of a sewing machine according to the invention, and

FIG. 2 is a left side view partly in cross section of the apparatus shown in FIG. 1.

According to the invention a sewing machine is provided having a sewing head and associated needle drive means for reciprocating a sewing needle. The machine includes a rotatable sewing table, preferably in the form of a cylindrical drum, having a curved surface for supporting material to be sewn. The curved surface has a slot therein to permit the needle to pass therethrough when it is reciprocated. The machine further includes clamping means for holding the material to be sewn against the curved surface.

A material supporting member is provided for rapidly feeding material into register with the curved surface of the sewing table and beneath the clamping means, prior to engaging the clamping means to clamp the material to the sewing table. Means are also provided for retracting the material supporting member after the clamping means has been engaged.

Referring to the drawings and particularly to FIG. 1, a sewing machine is shown having a sewing head 12, including a needle drive means for reciprocating a sewing needle 11. The machine includes a rotatable sewing table 14 having a curved sewing surface for supporting the material to be sewn. The table, which is preferably in the form of a cylindrical drum, has a slot in the curved surface thereof to permit the needle to pass therethrough when it is reciprocated. Clamping means 16 is associated with the sewing table for holding the material to be sewn against the curved surface thereof.

The clamping means 16 is provided with a slot 13 which is aligned with the slot in the curved surface of table 14. It should be noted that while table 14 is rotatable, the same is moved in discreet pulses or steps as the sewing needle reciprocates, but does not rotate through a complete revolution in its operation. Instead, the table 14 rotates until the same reaches the end of the slot 13 as shown in FIG. 1. In doing this, a plurality of penetrations of needle 11 occur through slot 13 as well as through the slot in the table as the same moves a distance of less than one complete revolution. The limiting distance through which the table 14 and clamp 16 can move is the arcuate length of slot 13. The machine also includes a standard bobbin case and hook assembly 17 which can be removed and replaced through the opening 19 in the wall of table 14.

A material supporting member is provided for rapidly guiding material to be sewn into register with the curved surface of the sewing table and beneath the clamping means. This member includes a plurality of curved blades 18a, 18b and which are formed of thin stock in order to receive the material to be sewn. The curved blades are mounted upon a pair of discs 20 and 22 which are in turn mounted upon one end of axially moveable inner shaft 50. The opposite end of shaft 50 is connected at 24 to the piston 27 of a pneumatic cylinder 28 having pressure ports 29 and 31. Shaft 50 is slideable within outer rotatable shaft 60. To facilitate alignment and reduce friction, inner shaft 50 may be supported by tiny bearings (not shown) press fit into the outer shaft 60 adjacent each end thereof. In operation, when port 31 is pressurized, it forces piston 27 into cylinder 28 and thereby axially moves the inner shaft 50 toward the sewing head until the blades 18a, 18b, and 180 come into register beneath clamping means 16, with the curved sewing surface of table 14.

After the clamping means 16 has been energized to clamp the material and blades against the sewing surface, port 29 is pressurized to force the piston 27 and shaft 50in the opposite direction so as to retract the blades 18a, 18b, and 1&- away from the sewing table. The blades are formed of a hard smooth material such that they can be retracted while the clamping means 16 is engaged and slip away from the material to be sewn, leaving the material remaining beneath the clamping means.

The clamping means 16 is formed of a circular strip of smooth spring steel, although a hard plastic may also be utilized. The strip has its lower end positioned between a pair of plates 39 and 40. Upper plate 39 is mounted upon a vertically moveable piston 38 of valve 36, such that when valve 36 is energized the piston 38 moves downward forcing the clamping strip against the lower plate 40 and thereby forces the upper surface of strip 16 to tightly hold material against the sewing surface of table 14. Valve 36 may be'a solenoid valve, air cylinder or similar device.

The sewing table 14 may be driven through appropriate gearing and linkage by the same motor which powers the nee dle drive. In this manner the table will move in discrete pulses in synchronism with the movement of the needle. Alternatively, the table can be driven by drive means D connected by pulley 64 and belt 63 to outer rotatable shaft 60 which is rotatably mounted within bearings 32 and 34.

The drive means in this case is preferably a stepping motor which may be of the electrical, pneumatic or fluidic type. The purpose of the stepping motor is to cause the sewing table to rotate in distinct pulses or steps. Control means (not shown) is connected between the stepping motor of the needle drive means in order to synchronize the movement of the sewing table with the stroke of the needle such that the table moves only when the needle is out of contact with the material to be sewn. The control means may be of the mechanical, electrical or pneumatic type.

A particularly useful control system is described and claimed in copending application Ser. No. 848,998, filed of even date herewith in the name of David C. Kamena and comprises a magnetic pick-up unit affixed to the sewing machine head which sends an electrical signal to a controller for the stepping motor whenever the sewing needle passes on the up stroke out of the material.

In operation, the material to be sewn, e.g., a cuff, is inserted over the narrow ends of blades 18a, 18b, and 18c. Thereafter the outer disc 22 is rotated slightly either manually or by automatic means such as a pneumatic cylinder actuated through gas lines 49 and 51 to make the material hold tightly against the blades and thus prevent puckering. The clamping rod 46 is moved inwardly to further prevent the material from moving on the blades. While the clamping means 16 is in a disengaged position, pneumatic cylinder 28 is energized by pressurizing port 31. This causes the blades and material affixed thereto to move toward the sewing head until they engage the sewing surface beneath the clamping means 16. At this point the valve 36 is energized causing piston 38 to move the upper clamping plate 39 downwardly forcing the clamping strip 16 against the lower plate 40 thereby resulting in the clamping means 16 tightly engaging the material to be sewn and the blades 18a, 18b and 180 against the sewing surface of table 14. The valve 36 is energized by pressurizing gas line 43. The clamping rod 46 is now opened to enable the blades of the material supporting member to be separated and retracted away from the material. The retraction thereof takes place upon the pressurization of cylinder 28 through port 29. The drive means is thereafter actuated and the material is sewn. Upon the completion of the sewing operation, gas line 41 is pressurized causing the upper plate 39 to move the clamping strip upwardly disengaging same from contact with the material. The material is thereafter removed from the sewing table and the process repeated.

It can be seen that the invention enables the art to rapidly feed a collar, cuff or similar shaped material into engagement with the sewing table in alignment with the sewing needle. Since the sewing table is curved, the material can be easily sewn without the usual puckering.

While the invention has been described in connection with the specific sewing machine illustrated in the drawings, it is obvious that many changes may be made and that certain parts may be used without others without departing from the spirit and scope of the invention.

What is claimed is:

1. In a sewing machine having a sewing head including needle drive means for reciprocating a sewing needle, the improvement which comprises a rotatable sewing table having a curved surface for supporting material to be sewn, said curved surface having a slot therein for the needle to pass through when it is reciprocated, and slotted clamping means for holding the material to be sewn against said curved surface.

2. A sewing machine as claimed in claim 1 wherein said rotatable sewing table comprises a cylindrical drum.

3. A sewing machine as claimed in claim 1 further including a material supporting member for feeding material into register with the curved surface of the sewing table and beneath said clamping means.

4. A sewing machine as claimed in claim 3 wherein said material supporting member includes means for axially moving it toward and retracting it away from engagement with the sewing table.

5. A sewing machine as claimed in claim 4 wherein said means for moving the material supporting member comprises a shaft slideably mounted upon the sewing table beneath said curved surface. 7 I

6. A sewing machine as claimed in claim 4 further including means for clamping material to said material supporting member.

7. A sewing machine as claimed in claim 4 wherein said material supporting member includes a plurality of curved blades adapted to slide over the curved surface of the sewing table and beneath said clamping means before the same is engaged to clamp material to the sewing table.

8. A sewing machine as claimed in claim 5 further including a pneumatic cylinder having a piston connected to said shaft for axially moving the material supporting member into register with the curved surface of the sewing table and for retracting same after the clamping means is engaged to clamp the material to the curved surface of the sewing table.

9. A sewing machine as claimed in claim 1 further including drive means for moving said sewing table in discrete steps in order to move material to be sewn into the path of said reciprocating needle. 

1. In a sewing machine having a sewing head including needle drive means for reciprocating a sewing needle, the improvement which comprises a rotatable sewing table having a curved surface for supporting material to be sewn, said curved surface having a slot therein for the needle to pass through when it is reciprocated, and slotted clamping means for holding the material to be sewn against said curved surface.
 2. A sewing machine as claimed in claim 1 wherein said rotatable sewing table comprises a cylindrical drum.
 3. A sewing machine as claimed in claim 1 further including a material supporting member for feeding material into register with the curved surface of the sewing table and beneath said clamping means.
 4. A sewing machine as claimed in claim 3 wherein said material supporting member includes means for axially moving it toward and retracting it away from engagement with the sewing table.
 5. A sewing machine as claimed in claim 4 wherein said means for moving the material supporting member comprises a shaft slideably mounted upon the sewing table beneath said curved surface.
 6. A sewing machine as claimed in claim 4 further including means for clamping material to said material supporting member.
 7. A sewing machine as claimed in claim 4 wherein said material supporting member includes a plurality of curved blades adapted to slide over the curved surface of the sewing table and beneath said clamping means before the same is engaged to clamp material to the sewing table.
 8. A sewing machine as claimed in claim 5 further including a pneumatic cylinder having a piston connected to said shaft for axially moving the material supporting member into register with the curved surface of the sewing table and for retracting same after the clamping means is engaged to clamp the material to the curved surface of the sewing table.
 9. A sewing machine as claimed in claim 1 further including drive means for moving said sewing table in discrete steps in order to move material to be sewn into the path of said reciprocating needle. 